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<span id="more"></span>


        <h5 id="基本特点"   >
          <a href="#基本特点" class="heading-link"><i class="fas fa-link"></i></a><a href="#基本特点" class="headerlink" title="基本特点"></a>基本特点</h5>
      <ul>
<li><p>ES6 的 class 可以看作只是一个语法糖，它的绝大部分功能，ES5 都可以做到，新的 class 写法只是让对象原型的写法更加清晰、更像面向对象编程的语法而已。ES6 的类，完全可以看作构造函数的另一种写法。</p>
</li>
<li><p>构造函数的 prototype 属性，在 ES6 的“类”上面继续存在。事实上，类的所有方法都定义在类的 prototype 属性上面。在类的实例上面调用方法，其实就是调用原型上的方法。</p>
</li>
<li><p>prototype 对象的 constructor 属性，直接指向“类”的本身，这与 ES5 的行为是一致的。</p>
</li>
<li><p>类的内部所有定义的方法，都是不可枚举的</p>
</li>
<li><p>类必须使用 new 调用，否则会报错。</p>
</li>
</ul>

        <h5 id="constructor-方法"   >
          <a href="#constructor-方法" class="heading-link"><i class="fas fa-link"></i></a><a href="#constructor-方法" class="headerlink" title="constructor 方法"></a>constructor 方法</h5>
      <ul>
<li>constructor 方法是类的默认方法，通过 new 命令生成对象实例时，自动调用该方法。一个类必须有 constructor 方法，如果没有显式定义，一个空的 constructor 方法会被默认添加。</li>
</ul>

        <h5 id="注意点"   >
          <a href="#注意点" class="heading-link"><i class="fas fa-link"></i></a><a href="#注意点" class="headerlink" title="注意点"></a>注意点</h5>
      <ol>
<li><p>严格模式<br>类和模块的内部，默认就是严格模式，所以不需要使用 use strict 指定运行模式。</p>
</li>
<li><p>不存在提升<br>类不存在变量提升（hoist），这一点与 ES5 完全不同。</p>
</li>
<li><p>name 属性<br>由于本质上，ES6 的类只是 ES5 的构造函数的一层包装，所以函数的许多特性都被 Class 继承，包括 name 属性。</p>
</li>
<li><p>Generator 方法</p>
</li>
</ol>
<p>如果某个方法之前加上星号（*），就表示该方法是一个 Generator 函数。</p>
<ol start="5">
<li>this 的指向<br>类的方法内部如果含有 this，它默认指向类的实例。但是，必须非常小心，一旦单独使用该方法，很可能报错。</li>
</ol>
<p>– 摘自 阮一峰 ECMAScript 6 (ES6) 标准入门教程 第三版 (<span class="exturl"><a class="exturl__link"   target="_blank" rel="noopener" href="https://www.bookstack.cn/read/es6-3rd/spilt.1.docs-class.md" >https://www.bookstack.cn/read/es6-3rd/spilt.1.docs-class.md</a><span class="exturl__icon"><i class="fas fa-external-link-alt"></i></span></span>)</p>
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